Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1750817AbWBQRk5 (ORCPT ); Fri, 17 Feb 2006 12:40:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1750818AbWBQRk4 (ORCPT ); Fri, 17 Feb 2006 12:40:56 -0500 Received: from master.soleranetworks.com ([67.137.28.188]:42410 "EHLO master.soleranetworks.com") by vger.kernel.org with ESMTP id S1750817AbWBQRk4 (ORCPT ); Fri, 17 Feb 2006 12:40:56 -0500 Message-ID: <43F617FA.2030609@wolfmountaingroup.com> Date: Fri, 17 Feb 2006 11:37:46 -0700 From: "Jeff V. Merkey" User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.6) Gecko/20040510 X-Accept-Language: en-us, en MIME-Version: 1.0 To: "linux-os (Dick Johnson)" Cc: Linux kernel Subject: Re: C/H/S from user space References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3871 Lines: 138 Dick, The model Netware uses for large drives for calculating C/H/S addressed this problem years ago and provides more useful output, since C/H/S is converted into a hieristic which acts almost like an MD5 hash and for a given dimension, does provide unique output for even very large drives. Code Attached. Jeff ULONG SetPartitionTableGeometry(BYTE *hd, BYTE *sec, BYTE *cyl, ULONG LBA, ULONG TracksPerCylinder, ULONG SectorsPerTrack) { ULONG offset, cylinders, head, sector; if (!cyl || !hd || !sec) return -1; cylinders = (LBA / (TracksPerCylinder * SectorsPerTrack)); offset = LBA % (TracksPerCylinder * SectorsPerTrack); head = (WORD)(offset / SectorsPerTrack); sector = (WORD)(offset % SectorsPerTrack) + 1; if (cylinders < 1023) { *sec = (BYTE)sector; *hd = (BYTE)head; *cyl = (BYTE)(cylinders & 0xff); *sec |= (BYTE)((cylinders >> 2) & 0xC0); } else { *sec = (BYTE)(SectorsPerTrack | 0xC0); *hd = (BYTE)(TracksPerCylinder - 1); *cyl = (BYTE)0xFE; } return 0; } ULONG SetPartitionTableValues(struct PartitionTableEntry *Part, ULONG Type, ULONG StartingLBA, ULONG EndingLBA, ULONG Flag, ULONG TracksPerCylinder, ULONG SectorsPerTrack) { Part->SysFlag = (BYTE) Type; Part->fBootable = (BYTE) Flag; Part->StartLBA = StartingLBA; Part->nSectorsTotal = (EndingLBA - StartingLBA) + 1; SetPartitionTableGeometry(&Part->HeadStart, &Part->SecStart, &Part->CylStart, StartingLBA, TracksPerCylinder, SectorsPerTrack); SetPartitionTableGeometry(&Part->HeadEnd, &Part->SecEnd, &Part->CylEnd, EndingLBA, TracksPerCylinder, SectorsPerTrack); return 0; } linux-os (Dick Johnson) wrote: >For those who think that C/H/S translation is useful, >attached is a simple program that gets whatever the BIOS >used from user-space. If you have large media (most do), >you will descover that C/H/S is useless because it is >always set to "MAX" like this: > > Disk parameter table(s) at vector 0x41 >Disk0 > Cylinders = 1024 > Sectors = 63 > Heads = 255 >Write precomp = 0 > Landing zone = 65296 > Reserved bit 0 set > Reserved bit 1 set > Reserved bit 2 set > More than 8 heads > Reserved bit 4 set > Defect map present > Disable retries > Disable retries >Disk1 > Cylinders = 306 > Sectors = 1 > Heads = 4 >Write precomp = 0 > Landing zone = 12544 > Disk parameter table(s) at vector 0x46 >Disk0 > Cylinders = 306 > Sectors = 1 > Heads = 4 >Write precomp = 0 > Landing zone = 12544 >Disk1 > Cylinders = 306 > Sectors = 1 > Heads = 4 >Write precomp = 0 > Landing zone = 12544 > > >Cheers, >Dick Johnson >Penguin : Linux version 2.6.15.4 on an i686 machine (5589.55 BogoMips). >Warning : 98.36% of all statistics are fiction. >_ > > > >**************************************************************** >The information transmitted in this message is confidential and may be privileged. Any review, retransmission, dissemination, or other use of this information by persons or entities other than the intended recipient is prohibited. If you are not the intended recipient, please notify Analogic Corporation immediately - by replying to this message or by sending an email to DeliveryErrors@analogic.com - and destroy all copies of this information, including any attachments, without reading or disclosing them. > >Thank you. > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/